Expired air collector and method of making the same



W. C. JONES July 16, 1968 EXPIRED AIR COLLECTOR AND METHOD OF MAKING THESAME 5 Sheets-Sheet 1 Original Filed Aug. 17, 1964 E m E V m WILLIAM C.JONES BY AT T Y s July 16, 1968 w. c. JONES 3,393,108

EXPIRED AIR COLLECTOR AND METHOD OF MAKING THE SAME Original Filed Aug.17, 1964 3 Sheets-Sheet 2 FIG.4

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ATT'YS W. C. JONES July 16, 1968 EXPIRED AIR COLLECTOR AND METHOD OFMAKING THE SAME 3 Sheets-Sheet 5 Original Filed Aug. 17, 1964 ATT'YSUnited States Patent 01 fice 3,393,108 Patented July 16, 1968 3,393,108EXPIRED AIR COLLECTOR AND METHOD OF MAKING THE SAME William C. Jones, 16W. 328 Walnut Lane, Timber Trails, Elmhurst, Ill. 60126 Originalapplication Aug. 17, 1964, Ser. No. 390,132, now

Patent No. 3,321,976, dated May 30, 1967. Divided and this applicationAug. 16, 1966, Ser. No. 572,784

3 Claims. (Cl. 156-253) ABSTRACT OF THE DISCLOSURE A method ofperforating an uninflated plastic bag intended for use as a component ofequipment for collecting and analyzing expired air. Selectiveperforation of one wall of the bag without perforating or damaging theother wall lying directly therebeneath is achieved by first affixing aplastic patch to the top wall, the patch having a pre-formed opening andbeing secured to the top wall in a narrow zone about that opening.Thereafter, the patch is lifted by its peripheral tab portion to pullthe top wall of the bag away from the wall lying directly therebeneathwhile, at the same time, a tool is brought into engagement with theportion of the top wall within the limits of the patch opening torestrain and thereby perforate the top wall portion disposed within suchopening.

This application is a division of my co-pending application Ser. No.390,132, filed Aug. 17, 1964, now US. Patent 3,321,976.

This invention relates to the method of fabricating components of adevice for collecting a quantity of exhaled air from a subject for thepurpose of analyzing the carbon dioxide content thereof, or for anyother suitable test purposes.

The equipment commonly used for collecting exhaled or expired air from asubject normally consists of a mouthpiece, an air-control valveconnected to the mouthpiece, and a container for collecting the airpassing through the valve. In the past, the containers have been bulkyand expensive, the connections between such containers and the valveassemblies have been fairly complex, in order to insure a leak-proofseal between the parts, and the valve units have been expensive tomanufacture and purchase, and have frequently presented problems ofmanipulation and cleaning for the user. The valve assemblies customarilyused with such breathing equipment ordinarily employ tapered valvemembers which are rotatably received in casings having tapered valveseats, the combinations therefor being in the nature of standardstopcock constructions to insure an airtight fit between the parts. Suchparts are normally ground or lapped together, with the result that theassemblies are expensive to manufacture and are composed of parts whichcannot be interchanged with the components of other similar assemblies.

Cleaning of the parts therefore presents problems for a user since caremust be taken to avoid co-mingling of the components of similarassemblies. Furthermore, even when properly matched parts are assembledtogether, sticking of such parts frequently occurs and such stickingoften requires interruption and re-running of the tests.

It is a principal object of the present invention to provide an expiredair collector which is relatively inexpensive and trouble-free inconstruction and operation and, specifically, to provide a method forfabricating a basic component or components of such a device. Inparticular, it is an object to provide a disposable air-collection bag,and its method of manufacture, which includes a highlyeffectiveconnecting means for sealing the coupling of the bag with a valve unit.

Other objects will appear from the specification and drawings in which:

FIGURE 1 is a perspective view of a collector assembly including adisposable bag formed by the method of the present invention;

FIGURE 2 is an exploded perspective view of the parts illustrated inFIGURE 1;

FIGURE 3 is a vertical sectional view of the valve unit;

FIGURE 4 is a rear elevational view taken along line 44 of FIGURE 3;

FIGURE 5 is an elevational view similar to FIG- URE 4 but illustratingthe parts in a different position of adjustment;

FIGURE 6 is a perspective view, taken partly in section, illustratingthe disposable bag component of the collector assembly prior toperforation of that bag;

FIGURE 7 illustrates the step of perforating the bag;

FIGURE 8 is a broken sectional view illustrating the perforating action;and

FIGURE 9 is a fragmentary elevational view of the complete assemblyshowing the collector bag in section to reveal the sealing relationshipbetween the parts.

Referring to the drawings, the air collector assembly essentiallycomprises a valve unit A, a mouthpiece tube assembly B mounted on thevalve unit, and an air collection bag C. In use, all three componentsare assembled in the relationship illustrated in FIGURE 1.

The valve unit A comprises a pair of valve members 10 and 11 having fiatopposing surfaces 12 and 13 in contiguous relation. The parts are joinedfor relative rotation about an axis normal to the plane of thesecontiguous surfaces by means of a connecting assembly 14 as shown inFIGURE 2.

The connecting assembly comprises a bolt or threaded stud 15, anadjustment nut 16, and a spring member 17. Bolt 15 extends through thealigned apertures 18 and 19 of valve members 10 and 11, and spring 17,which is interposed between the knurled adjustment nut 16 and the rearface of valve member 11, urges the opposing faces of the two valvemembers into snug sealing contact. When disassembly of the parts isdesired, nut 16 is simply unthreaded from bolt 15, permitting separationof the major components 10 and 11 as illustrated in FIGURE 2.

Valve member 10 is preferably formed from a suitable molding plasticsuch as polystyrene or an acrylic resin and has a cylindrical-shapedbody portion 10a and an integrally-formed depending handle portion 10b.Opening 18 extends along the axis of cylindrical portion 10a.

Valve member 11 is similarly formed of plastic material and alsoincludes a cylindrical body portion 11a and radially-extending handle11b. In the illustration given, handle 11b is in the form of a steppedmetal shaft having one end thereof cemented or otherwise anchored in aradial bore 20 provided in the valve member.

Mouthpiece B is composed of two parts: a metal tube 21 which isconnected at one end to valve member 10 and which projects rearwardlytherefrom, and a plastic sleeve 22 which is fitted over the free end ofthe metal breathing tube. Referring to FIGURES 2 and 3, it will be seenthat the cylindrical body of valve member 10 is provided with a passage23 extending longitudinally therethrough along a line spaced between thecentral axis of the body and the cylindrical periphery thereof. The rearend portion of the passage or bore is enlarged and tightly receives theforward end of breathing tube 21. While a tight frictional interfitbetween the parts is adequate to maintain them in operativerelationship, the forward end of the breathing tube may, if desired, becemented or otherwise permanently secured within the enlargement of thebore.

The rear end of the breathing tube is flattened slightly so that whenviewed in transverse section it defines a horizontally-extendingellipse. The mouthpiece sleeve 22 is composed of a deformable plasticmaterial such as polyvinyl chloride and readily conforms to the shape ofthe tubes rear end portion when the sleeve is slipped in place (FIGURE1). In use, the clear plastic sleeve projects rearwardly a shortdistance beyond the free end of the breathing tube. The sleeve therebyforms a protective covering for that portion of the breathing tube to beplaced into a subjects mouth. After use of the air-collecting device,the disposable plastic sleeve is simply removed and discarded and a newsleeve is slipped in place.

Cylindrical valve member 11 is provided with a passage 24 extending inan axial direction therethrough, the passage being disposed between therotational axis of the member and the periphery thereof. As shown inFIGURE 3, passage 24 is in register with passage 23 of valve member 10when the valve is in an open condition. As valve member 11 is rotatedwith respect to member 10, their respective passages 24 and 23 are movedout of alignment and opening 25 is brought into register with passage 23(FIGURE As shown most clearly in FIGURE 2, opening 25 extends in anaxial direction through valve member 11 and is spaced circumferentiallyfrom flow passage 24. Opening 25 and passage 24 are of equal radialdistances from the rotational axis of the valve member so that rotationof the valve member 11 over an arc of approximately 90 degrees willplace either opening 25 or flow passage 24 in direct communication withpassage 23 and mouthpiece B. To limit the extent of rotation of thevalve member 11 with respect to valve member 10, the handle portion a isprovided with a forwardly-projecting stop pin 26 (FIGURES 4 and 5). Whenpassage 24 communicates with the mouthpiece, the stop pin is engaged byhandle 11b (FIGURE 4). A radially-extending stop member 27 projectsoutwardly from the periphery of valve member 11 from a point spacedcircumferentially approximately 90 degrees from handle 1111. Therefore,when the valve member 11 has been rotated approximately 90 degrees fromthe position illustrated in FIGURE 4, the radial stop member 27 engagespin 26 and prevents further rotation of the valve member 11 in the samedirection. When stop pin 26 is engaged by member 27, the opening of thevalve member is in communication with mouthpiece B through the passage23 of valve member 10. In this manner a gas to be rebreathed can beintroduced in the bag, saved gas-tight until rebreathed, then savedagain until time is convenient for analysis.

A generally cylindrical probe tube 28 projects forwardly from valvemember 11 and has its rear end portion received and secured withinpassage 24. As shown in FIG- URE 3, the probe tube is provided with anaxial opening 29 at its free end as well as with lateral openings 30. Itwill also be observed that the free end portion of the probe tube 28 isrounded to facilitate insertion of the probe into the opening of bag C.

Because of its length, handle 11b is the principal means for grippingvalve member 11 and rotating it with respect to valve member 10.However, to the extent that stop member 27 projects radially from valvemember 11, it may be used as an auxiliary or alternate handle foroperating the valve.

Handle 11]) functions not only as an operating lever but also as afitting for coupling the valve to a spirometer or to some other devicefor analyzing the air collected in bag C. For this purpose, the steppedhandle has a flow passage 31 extending axially therethrough and thispassage communicates with passage 24 of the valve member 11 by means ofradial bore 20. Thus, when the valve is adjusted into the positionillustrated in FIGURES 3 and 4, both the probe 28 and the tubular handle11b communicate with the mouthpiece B through passages 24 and 23 of thevalve members. To facilitate connection of the tubular handle to aspirometer or other measuring device,

4 the distal portion of the stepped handle is tapered slightly (FIGURE3). This portion of the handle may therefore be readily inserted orplugged into the socket of the analytical device (not shown).

Bag C is formed from a polyester film and is completely sealed exceptfor a single reinforced opening 32 in the side wall thereof. Thepolyester film, used because of its gas-impermeable properties, isrelatively hard and non-stretchable. To reinforce opening 32 and toprovide an effective means for sealingly attaching the bag to probe 28,I therefore laminate a patch 33 on the bags surface. The patch is formedfrom a resilient and slightly elastic plastic material such as polyvinylchloride and is provided with an opening 34 of a diameter slightlysmaller than the outside diameter of probe 28. The patch is sealed tothe bag by heat-sealing or by suitable adhesives in the zone immediatelyadjacent the periphery of opening 34. As shown in FIGURE 9, theoutermost portions of the patch remain unsealed to the bag and therebydefine tab portions 33a.

Insertion of the probe 28 into the bag through opening 34 of the patchcauses a stretching of the patch about-the surface of the probe. InFIGURE 9 it will be seen that the patch stretches inwardly about theprobe to define a tensioned collar 33b. It has been found that theformation of such a collar results in an effective air-tight sealbetween the bag and the inserted probe.

FIGURES 6-8 illustrate certain steps in the formation of the opening inbag C. As indicated by the sectioning of the bag, the bag may be formedas a segment of a continuous tube, each individual bag being cut fromthe tube and heat-sealed along spaced heat-sealing zones 35 to form acompletely imperforate bag structure. Thereafter, patch 33 with itspreformed opening 34 is cemented or otherwise sealed to the outersurface of the bag. A tab portion 33a of the patch is then lifted eithermanually (as shown) or mechanically, the lifting action serving toseparate opposite walls of the bag so that only one wall will beperforated by the flat spatula-like tool 36. The wall of the bag towhich the tab is afiixed is lifted into contact with the end of thetool, or the tool may be lowered into contact with the bag, or both,until the end of the tool bears against the unperforated wall of the bagwithin the opening 34 of the patch. Then, by continuing the downwardmovement of the tool and/or the upward movement of the bags upper wall,the end of the tool tears the Wall of the bag to form opening 32 andflap 37 (FIGURE 8). Since the film from which the bag is formed is thin(preferably 0.0005 of an inch in thickness), flap 37 is of noconsequence and does not in any way interfere with the cooperativeaction of patch 33 and probe 28 when the bag and valve unit areconnected together.

In operation of the air-collecting assembly, an operator first insertsprobe 28 through opening 34 of the patch until the lateral apertures 30of the probe are well within the bag. Valve member 11 is rotated intothe position illustrated in FIGURE 5 so that mouthpiece B communicateswith passage 25 which in turn communicates with the atmosphere. Asubject, holding the apparatus by means of handle 10b, breathes severaltimes through mouthpiece B until he becomes accustomed to the device andhis breathing pattern reaches a normal level. Handle lever 11b is thenswung clockwise (when viewed in FIG- URE 4) to bring the mouthpiece intodirect communication with probe 28 and bag C. The exhaled air flowsdirectly into the bag and is collected therein. Since the passage of theprobe 28 is substantially larger in crosssectional dimensions than thatof handle-fitting 11b, and since no significant back pressure is exertedby the walls of the bag C, there is no significant leakage of airthrough handle 11b at the time the bag is being filled.

As soon as a sufficient quantity of air has been collected in the bag,valve member 11 is rotated in the position illustrated in FIGURE 5,thereby blocking the flow of gas between the mouthpiece and the bag.Handlefitting 11b, which remains in constant communication with passage24 and probe 28, is simply inserted into the socket of the gas analysisequipment (not shown) and the air collected in the bag is expelledthrough the handle by applying a slight pressure to the bags side walls.The configuration of collar 33b permits substantial pressure with nosignificant leakage of air as its inward shape increasingly tightens ina check valve action.

After the air collected in the bag has been analyzed, the bag isdisconnected from the probe and is discarded. Similarly, the plasticsleeve 22 is removed from mouthpiece tube 21 and is also discarded.

Since the pressures involved in the operation of the apparatus arerelatively low, and since the valve members 10 and 11 have large surfaceareas in mutual contact, there is no leakage of air between the flatopposing surfaces of such members. If desired, a small amount of alubricant may be smeared upon the opposing surfaces of the valve membersto insure further against any possibility of leakage as well as tolubricate the parts for relative movement.

Interchangeability of the valve members is readily achieved because ofthe fact that the contacting surfaces of such parts are fiat. Thus,valve member 10 may be operatively connected to a valve member 11 whichis either a replacement part or which is taken from another valveassembly, without encountering problems of mismatching and withoutdanger that leakage will occur because of the substitution.

While in the foregoing I have disclosed an embodi ment of the inventionin considerable detail for purposes of illustration, it will beunderstood by those skilled in the art that many of these details may bevaried without departing from the spirit and scope of the invention.

I claim:

1. In a method of perforating a wall of a completely sealed plastic bag,the steps of securing a plastic patch having a pre-formed openingtherein upon a wall of said bag, said patch having a tab portionoverlying said wall and projecting laterally beyond the zone ofsecurement between said patch and wall, and thereafter lifting saidpatch by said tab portion while at the same time urging a perforatingtool into contact with the wall of said bag within the limits of saidpatch opening.

2. In a method of perforating a wall of a fiat and completely sealedplastic bag, the steps of positioning a flat patch having a pre-formedopening therein upon a wall portion of said bag, securing said patch tosaid wall portion in a narrow zone extending about said opening while atthe same time leaving a peripheral portion of said patch unsecured tosaid bag, and thereafter lifting said patch by the peripheral portionthereof while at the same time urging a perforating tool into contactwith the wall portion of said bag within the limits of said patchopening.

3. In a method for selectively perforating one wall of a plastic bagdisposed in superimposed engagement with a second wall thereof withoutalso perforating said second Wall, the steps of positioning a patchhaving a pre-formed opening therein upon the outer surface of said onewall, securing said patch to said one wall in a narrow zone extendingabout said opening, urging a tool into contact with a portion of saidone wall in the area defined by said patch opening to restrain movementof said portion away from engagement with said second wall, andthereafter drawing said one wall by said patch away from said secondwall while said tool is in engagement with said portion to perforatesaid one wall in the area defined by the opening of said patch.

DOUGLAS 1. DRUMMOND, Primary Examiner.

